Is There A Device For Home Use That Can Measure How Low The Bass In My Speakers Is?

OP wants HZ but gets SPL (“I didn’t order umm”) suggestions as though he were the brain dead one. LOL. 

OP, there are free versions of tone generators, SPL meters and spectrum analyzers available in the Apple App Store or Google Apps. HSU Research has a test tone CD that has the absolute cleanest 16HZ recordings on the planet, should you be interested in the extreme. I’ve gotten one free with every sub. Probably available for sale on the cheap. It has a bunch of other test pieces as well including music and pink/white noises. In the event you’re looking at 20HZ and up, the free stuff will do nicely. 

(Mr. Anderson was here.)

B weighted is the method used in stereophile in my experience reading the magazine. A weighted is used at times as well. But this is all nonsense. Mentioning it is nothing more than adding your own attaboy. SPL  and spectrum analyzers made for audio are not going to have to be taken off construction mode in order to measure your speakers. My dB meter has an OSHA mode, among others, but it is still measuring music…because that’s what it was meant for. Buy or download music related products and stay off PPG, manufacturing, farming, aviation and construction safety we stores and you’re golden. A simple google search turns up excellent no brained results. I believe you’d have to go out of your way to mess this up in the way you suggested.
 

https://www.stereophile.com/content/measuring-loudspeakers-part-one-page-4ok